An ash cloud from an erupted volcano in Chile is continuing to disrupt flights in Australia and New Zealand.

Over the past two days, scores of flights have been cancelled and thousands of passengers have been left stranded.

Qantas Airways, Australia’s main carrier, resumed flights in and out of Melbourne but is still not flying to and from New Zealand or within the country.

The eruption of Mt Puyehue has already caused cancellations in South America with ash blanketing towns in neighbouring Argentina.

Air New Zealand’s domestic and international services have continued but domestic flights have been restricted to lower altitudes to avoid the ash.

“We will not fly through ash and are constantly taking guidance from CAA…to ensure we can continue to carry passengers only where safe routes and altitudes are available,” said Air NZ chief pilot David Morgan.

Flights across the Tasman from Wellington and Christchurch altered their paths to be further north than normal.

New Zealand’s Civil Aviation Authority said the cloud had moved higher with the base at around 27,000 feet from the previous 20,000-foot level.

“That gives the airlines a bit more flexibility on operations, but it is completely their decision on whether they fly,” spokesman Bill Sommer told Reuters.

Cathay Pacific also adjusted its flight routes, but continued to fly, while Emirates resumed flights after cancellations and says it will continue to monitor the situation.

The Virgin Australia group, including Pacific Blue resumed flights to New Zealand and parts of Australia this morning.

The volcano in the Puyehue-Cordon Caulle chain in Chile has been erupting for the past week, throwing South American air travel into chaos.

Peter Lechner of CAA says that aircraft should not be flying in the ash. “There is a danger of stalling the engines through a build-up of ash in the engines,” he said.

An estimated 60,000 travellers, mostly in Australia, have been affected, as around 200 flights were cancelled.

More than 20,000 passengers are stuck in a holding pattern, while terminals at Melbourne, Sydney and in Tasmania were transformed into makeshift hotels.

The Volcanic Ash Advisory Centre says its expect ash to clear from the Melbourne area overnight, but warn it could go on to affect Adelaide.

Last April, the eruption Icelandic volcano, Eyjafjallajokull, caused worldwide aviation chaos with 100,000 cancelled flights, affecting some 10 million people at a cost of $2 billion.

This was worse than the current disruption because it spread ash throughout the air column, from ground level to the upper atmosphere.